Recently, need for a communication carrier adapted to control route/resource of data traffic has been increasing. For example, it has been required that a redundant route is prepared in advance and the route is switched at high speeds in the event of a fault, thus realizing a high reliability, that the route/resource is separated for individual different services to realize virtuality and that the traffic load is dispersed and optimized by traffic engineering to improve the efficiency of resource utilization.
Also, for control of the route and resource, the communication carrier makes use of, for example, a path technique for plural L2 (Layer 2) virtuality rendering, thereby realizing high reliability of core network, presentation of a VPN (Virtual Private Network) service to enterprises and establishment of NGN (next Generation Network) transport. Known as such path techniques are, in the MPLS (Multi-Protocol Label Switching System), for example, MPLS, G-MPLS (Generalized Multi-Protocol Label Switching), MPLS-TP (MPLS-Transport Profile) and MPLS directed to transport: old T-MPLS (Transport-MPLS). Also, in the Ether system, VLAN (Virtual LAN), PB (Provider Bridging) (Q—in—Q), PBB (Provider Backbone Bridging) and MAC (Media Access Control)—in—MAC) are known.
Then, for example, in connection with a device for inter-work from VLAN network to MPLS network, it is disclosed that the MPLS level of output is determined from a set of VLAN ID and layer 3 layer 4 header information of a packet (see PATENT LITERATURE 1, for instance). Further, a technique is disclosed according to which, for example, a service identifier is allotted to a LSP (TE-LSP) for tunnel and a service identifier is allotted to path setting request signaling, so that only LSP's for which the TE-LSP has the same service identifier can be accommodated (see PATENT LITERATURE 2, for instance). Furthermore, a technique concerning PBT (Provider Backbone Transport) and MPLS is disclosed (see PATENT LITERATURES 3 and 4, for instance).